The present invention is directed towards an improved structure for coupling field windings to motor brushes.
Vacuum cleaners, hand-held power tools and other small electrically powered devices are often provided with motors having wound rotors that are energized through circuits which include carbon brushes which engage a commutator mounted on the rotor. In the standard construction, field windings which extend around the stator must be coupled to the carbon brushes. U.S. Pat. No. 4,800,312 describes an improved structure for automatically coupling the field windings to respective brushes.
In accordance with this patent, brush tube receptacles which house the brushes are formed with a V-shaped groove extending laterally from the brush tubes. As the brush tube receptacle is pushed into its plastic housing, the V-shaped groove snares and frictionally catches the field winding. While this simplifies the procedure for coupling the field winding to the brush tube, and represents a significant improvement over the prior art, the design sometimes proved unreliable due to the mechanical nature of the connection.